Mechanism for controlling the admission of fuel and air to internal combustion engines for highly volatile fuel



001.24, 1933. K E HESSELMAN 1,931,541

MECHANISM FOR CONTROLLING THE ADMISSION 0F FUEL AND AIR TO INTERNAL:COMBUSTION ENGINES FOR HIGHLY VOLATILE FUEL Filed May 6, 1930 I 1 g; 5 a19 Q: Z0 1J$ Et i 17.14"

I/Vl/E/VTOK. @M 44 MM war/M Patented Oct. 24, 1933 UNITED STATESMECHANISM FOR CONTROLLING THE AD- IWISSION F FUEL AND AIR- TO INTERNALCOMBUSTION VOLATILE FUEL ENGINES FOR HIGHLY Knut Jonas Elias Hesselman,Saltsjo-Storangen,

near Stockholm, Sweden Application May 6, 1930, Serial No. 450,146, andin Sweden May 7, 1929 16 Claims.

The present invention relates to internal combustion or explosionengines of the kind which are driven by highly volatile fuel.

The object of the invention is to provide a controlled injection of fueland combustion air so that the quantity of fuel admitted-to the enginefor each stroke will be properly adjusted in relation to the load and,in case of multicylinder engines, will be equal for all of thecylinders, and the quantity of air drawn in at each stroke will beproperly adjusted in relation to the quantity of fuel admitted for eachstroke. This will notonly reduce the consumption of fuel but will alsosecure proportionality between the quantities of fuel and air containedin the fuel charge supplied for each stroke over the entire workingrange of the engine.

The invention is characterized, chiefly, by the fact that the fuel isinjected into the'air inlet conduit of the engine by means of a pumpprovided with a regulating device which varies the quantity of fuel tobe injected for each stroke in accordance with the load of the engine,the air inlet conduit being provided with a spring operated airregulating device, the spring load of which is made dependent on theregulating device of the pump in such a way that, upon a reduction ofthe load of the engine to a predetermined degree, the quantity of airdrawn in during each suction period will be proportional orsubstantially proportional to the quantity of fuel injected for eachstroke. Other characteristic features of the invention will appear asthe following description proceeds.

In the accompanying rmawing a vertical section of a device embodyingthis invention is illustrated.

Mounted in the cover 2 of the cylinder 1 of the engine (not otherwiseshown) is the cylinder 4 inlet valve 3. Communicating with the air inletinlet pipe 5 which opens to the atmosphere at 6. Highly volatile liquidfuel is injected ,into the air inlet pipe 5 by means of a sprayingnozzle 7 fed from the fuel pump 8. The fuel pump is provided with adevice for regulating the quantity to be injected. As shown in thedrawing said device comprises a lever 10 cooperating with a disk orcollar on the pump plunger 9 which serves to limit the suction stroke ofthe plunger and a control lever 11 to adjust the lever 19 under manualcontrol or under the control of a governor. The suction stroke of theplunger 9 is effected in the embodiment shown by means of a spring 12and the delivery stroke is efiected by passage 4 formed in the cylindercover is the air a cam disk 13 driven from a shaft of the engine andoperating the plunger through the medium of a sliding block 14.

Provided inside the air inlet pipe 5 adjacent to the port 6 is aregulating device comprising a spring loaded valve plate 15 cooperatingwith a seat 16 surrounding the air inlet port 6. The valve plate 15 isslidably mounted on a stem 17 projecting to the outside of the valvecasing through a sleeve shaped projection 18 of the valve casing andbearing with its outer end against the control level 11. The valve plate15.is supported by a spring 19 resting on a disk 20 providing anabutment on the stem 17. Screwed on the threaded upper end of the stem 717 projecting above the valve plate 15 is a nut 21 serving as an upperstop for the valve plate. The stem 17 and associated parts maybe termeda movable carrier for the spring 19. I

When the engine operates at normal or full 7 load the air regulatingdevice is in the position shown. In this position the nut 21 maintainsthe valve 15 in its lowermost and fully open position. In this positionthe spring 19 is under no tension or under a slight tension only. Inother words, the valve in this position is rendered inefiective tocontrol flow of air to the inlet passage 4. If the load decreases andthe fuel pump regulating device is consequently operated to reduce theamount of fuel to be injected, by swinging the control lever 11 upwards,then the stem 17 will be moved upwards simultaneously. In this movementthe spring 19 will lift the valve plate 15 without any hindrance,causing it to throttle the air supply accordingly until it approachesthe seat 16. Upon further decrease of the quantity of fuel to beinjected, that is, upon continued upward move ment of the stem 17, thespring 19 will be put under tension so as to press the valve 15 againstits seat with a pressure that increases with continued upward movementof the stem 17 or, in other words, the spring tension acting on thevalve will correspond to a more and more re duced pressure within thecylinder. Thus, the valve will allow only such quantity of air to enteras is determined by the vacuum within the cylinder. By suitablyadjusting the spring tension, the quantity of air admitted to the airinlet pipe during each suction period will be substantially proportionalto the quantity of fuel injected for each stroke.

It will be observed that the distance of the abutment disk 20 from theair inlet opening 6 determines the amount of spring load on the valveplate 15 when the apparatus is in the range of its movement whereinthrottling" of the air takes place, and also that the valve constructionis such that the size of the opening for flow of air past the valvevaries proportionately with movement of the valve toward and away fromits seat. noted that the parts and 11 of the control .mechanism, theformer determining the length of the pump stroke and the latterdetermining the value of the spring load on the air valve, are arrangedso that their movements are in substantially direct proportion to eachother. This arrangement I find to be particularly effective forobtaining the desired results with mechanism of the utmost simplicityand practicability which involves no difficulty either in itsmanufacture or maintenance.

It is to be noted that many modifications may be made without departingfrom the principle of the invention. Thus, the design and arrangement ofthe pump or the air regulating device or both may be modified.

What I claim is:

1. In an internal combustion engine having a working cylinder, meansproviding a passage for supplying a mixture of volatile fuel and air tothe engine and having an inlet for air, pump means for supplying apredetermined quantity of fuel to said passage for each working strokeof the cylinder, control means for governing the quantity of fueldelivered by said pumping means for each working stroke of the cylinder,a valve for controlling said inlet, said valve being movable in responseto variations in pressure in said passage, a spring load acting on saidvalve under the influence of said control means for maintaining asubstantially constant ratio between the quantity of fuel and airsupplied for each such working stroke irrespective of variations inengine speed, and means for rendering said valve ineffective at highengine load.

2. In an internal combustion engine having a working cylinder, meansproviding a passage for supplying a mixture of volatile fuel and air tothe engine and having an inlet for air, pump means for supplying apredetermined quantity of fuel to said passage for each working strokeof the cylinder, control means for governing the quantity of fueldelivered by said pumping means for each working stroke of the cylinder,a valve for controlling said inlet, a spring for closing said valve, amovable carrier for said spring, said carrier being operativelyassociated with said control means so as to be moved with said controlmeans in a direction tending to close the valve when the control meansis moved to decrease the amount of fuel supplied, and means moving withsaid carrier for rendering said spring ineffective to close the valvewhen the control means is moved to a position for supplyingsubstantially full load fuel injection.

3. In an internal combustion engine, means providing 'a passage forsupplying a mixture of volatile fuel and air to an internal combustionengine and having an air inlet, a pump for injecting fuel into saidpassage, control means for varying the quantity of fuel delivered by thepump in accordance with variations in engine load, a valve forcontrolling the admission of air through said inlet, said valve beingmovable in response to variations in pressure in said passage, meansincluding a spring for moving said valve toward closed position, saidlast named Further, it is to be means being actuated by movement of saidcontrol means, and means for rendering said spring ineffective when thecontrol means is moved to a position providing substantially maximumfuel injection.

4. In an internal combustion engine having-a working cylinder, meansproviding a passage for supplyinga mixture of volatile fuel and air tosaid cylinder and having an air inlet, a plunger pump for injecting fuelinto said passage, control means for governing the length of theefifective stroke of said pump whereby to vary the quantity of fuelinjected per working stroke of the cylinder, a valve for governing theadmission of air through said inlet, a movable member adapted to beactuated by movement of said control means, said valve being carried bysaid member and movable relative thereto, means on said movable memberproviding a spring carrier and a spring between said carrier and saidvalve,

said spring tending to cause said valve to move with said carrier andpermitting said valve to move relative to said carrier when the valveapproaches its seat.

5. In an internal combustion engine having a working cylinder, meansproviding a passage for supplying a mixture of volatile fuel and air toan internal combustion engine and having an air inlet, a plunger pumpfor injecting fuel into said passage, control means for governing thelength of the effective stroke of said pump whereby to vary the quantityof fuel injected per working stroke of the cylinder, a valve forgoverning the admission of air through said inlet, said valve beingadapted to open due to differential air pressure caused by enginesuction, and a spring influenced by movement of the control means forapplying to said valve a closing pressure increasing as the fuel supplyis decreased, said valve being adapted to move to fully open positionwithout resistance from said spring when the control means is moved tosubstantially full load position. I

6. In an internal combustion engine having a working cylinder, meansproviding a. passage for supplying a mixture of volatile fuel and air tosaid cylinder and having an air inlet, a plunger pump for injecting fuelinto said passage, means comprising a rock shaft and an arm on saidshaft for govering the length of the eifective stroke of said pumpwhereby to vary the quantity of fuel injected per working stroke of thecylinder, a valve stem operatively associated with said rock shaft so asto move upon movement thereof, a valve for governing the admission ofair through said inlet, said valve being adapted to open due todifferential air pressure caused by engine suction and said valve beingslidably mounted on said valve stem, a spring carrier on said stem, ,aspring between said carrier and said valve, said spring tending to movesaid valve toward closed position, and valve retaining means on saidstem for rendering said spring ineflective to move said valve when thevalve stem is in predetermined positions of adjustment. r

'7. In an internal combustion engine having a working cylinder, meansproviding a passage for supplying a mixture of volatile fuel and air tosaid cylinder and having an air inlet, a plunger pump for injecting fuelinto said passage, means comprising a rock shaft and an arm on saidshaft for governing the length of the eflective stroke of said pumpwhereby to vary the quantity of fuel injected per working stroke of thecylinder, a valve stem operatively associated with said rock shaft .soas to move upon movement ,thereof,"a valve for governing the admissionof air through said inlet, said valve being adapted to open due todifierential air pressure caused by engine suction and said valve beingslidably mounted on said valve stem, a spring carrier on said stem, aspring between said carrier and said valve, said spring tending to movesaid valve toward closed position, and adjustable valve retaining meanson said valve stem for rendering said spring ineffective to close thevalve when the valve stem is moved to a position such that the distancefrom said spring carried to the valve seat exceeds a predeterminedvalue.

8. In an internal combustion engine having a working cylinder, meansproviding a passage for supplying a mixture of volatile fuel and air tothe engine and having an inlet for air, a .pump

for supplying a predetermined quantity of fuel to said passage for eachworking stroke of the cylinder, control means for governing the quantityof fuel delivered by said pump for each working stroke of the cylinder,a valve for controlling said inlet, a valve spring, a carrier for saidspring mounted to move in accordance with movement of said controlmeans, said carrier in one range of its movement operating through themedium of said spring, to cause movement of the valve with the carrierto closed position and in the remaining range of. its movement,operating to compress the spring to a variable degree between thecarrier and the valve.

9. The method of supplying a combustible mixture of volatile fuel andair to an internal combustion engine having a valve controlled air inletpassage which consists in injecting volatile fuel into said passage inpredetermined amounts variable in accordance with the load on theengine, applying a spring load to said valve tending to close it,varying the value of said load at low engine loads in accordance withvariations in the quantity of fuel supplied to maintain a substantiallyconstant ratio between the quantities of fuel and air supplied to saidpassage, and at high engine loads rendering said spring load ineffectivewhereby to permit an unrestricte'd supply of airto enter said passage.

10. That improvement in the method of supplying a combustible mixture ofvolatile fuel and air to an internal combustion engine by the aid of afuel injecting pump which consists in varying the quantity of fuelinjected by said pump in accordance with-variations in the load on theengine, admitting to the engine at engine loads above a predeterminedvalue an unrestricted supply of combustion air, and at engine loadsbelow said predetermined value restricting the supply of combustion airto said engine so as to maintain a substantially constant ratio of fueland air irrespective of engine speed.

11. In an internal combustion engine having a working cylinder, meansproviding a passage for supplying a mixture ofvolatile fuel and air tothe engine and having an inlet for air, pump means for supplying ameasured quantity of fuel to said passage for each working stroke of thecylinder, a valve for controlling said inlet,

said valve comprising a valve member adapted to open under the influenceof pressure of air admitted through said inlet and a spring load forclosing the valve, said valve providing an intive to control flow of airto said passage when let opening for fiow of air increasing in size insubstantially direct proportion with movement of said valve member awayfrom closed position, regulating mechanism for regulating said pumpmeans and said valve comprising parts operatively connected to move insubstantially directly proportional relationship with respect to eachother, the position of one of said parts determining the quantity offuel delivered by said pump means for each working stroke and theposition of the other of said parts determining the value of the springload on said valve member resisting opening of the valve and means forrendering said valve member inetfecsaid'regulating mechanism is adjustedto provide a fuel supply suitable for substantially full load operationof the engine.

12. In an internal combustion engine having a working cylinder, meansproviding a passage for supplying a mixture of volatile fuel and air tothe engine and having an inlet for air, pump means for supplying ameasured quantity offuel to said passage for each working stroke of thecylinder, a valve for controlling said inlet, said valve comprising areciprocable valve member adapted to open under the influence ofpressure of air admitted through said inlet and a spring load forclosing the valve, mechanism for regulating said pump means and saidvalve comprising parts operatively connected to move in substantiallydirectly proportional relationship with respect to each other, theposition of one of said parts determining the quantity of fuel deliveredby said pump means for each working stroke and the position of the otherof said parts determining the value of the spring load on said valvemember resisting opening of the valve and means for rendering said valvemember ineffective to control flow of air to said passage when saidregulating mechanism is adjusted to provide a fuel supply suitable forsubstantially full load operation of the engine.

13. In an internal combustion engine having a working cylinder, meansproviding a passage for supplying a mixture of volatile fuel and air tothe engine and having an inlet for air, pump means for supplying ameasured quantity of fuel to said passage for each working stroke of thecylinder, a valve for controlling said inlet, said valve comprising areciprocable valve member adapted to open under the influence ofpressure of air admitted through said inlet and a spring load forclosing the valve, said valve member and said inlet cooperating toprovide an inlet means and said valve comprising parts operativelyconnected to move in substantially directly proportional relationshipwith respect to each other, the position of one of said partsdetermining the quantity of fuel delivered by said pump means for eachworking stroke and the position of the other of said parts determiningthe value of the spring load on said valve member resisting opening ofthe valve, and means for rendering said spring load inefiective to movesaid valve member away from substantially fully open position when saidregulating means is adjusted to provide a fuel supply suitable forsubstantially full load operation of the engine.

14. 'In an internal combustion engine having a working cylinder, meansproviding a passage for supplying a mixture of volatile fuel and air tothe engine and having an inlet for air, pump means for supplying ameasured quantity of fuel to said passage for each working stroke of thecylinder, a valve for controlling said inlet,

said valve comprising a reciprocable valve member adapted to open underthe influence of pressure of air admitted through said inlet, a loadingspring and an abutment against which said spring reacts, said springtending to close said valve, the distance of said abutment from saidinlet opening determining the force due to 'air pressure required toopen the valve, regulating mechanism for regulating said pump and saidvalve comprising parts operatively connected to move in substantiallydirectly proportional relationship with respect to each other, the posi=tion oi one of said parts determining the quan-- tity oi fuel deliveredby said pump means for each working stroke or the cyinder, the positionor the other of said parts determining the distance between said inletopening and said abutment and said other of said parts determining adistance between said abutment and said valve opening sumcient to causesaid valve to be fully opened when said regulating mechanism is adiustedto provide a fuel supply suitable for substantially full load operationofthe engine.

15. In an internal combustion engine having a working cylinder, meansproviding a passage for supplying a mixture of volatile fuel and air tothe engine and having an inlet for air, pump means for supplying ameasured quantity of fuel to said passage for each working stroke of thecylinder, a valve for controlling said inlet, said valve comprising areciprocable valve member adapted to open under the influence ofpressure of air admitted through said inlet, a loading spring and anabutment against which said spring reacts, said spring tending to closesaid valve and said abutment being adjustable with respect to said inletopening to determine the force required to open the valve against theresistance provided by the loading spring, regulating mechanism forregulating said pump means and-said valve comprising parts operativelyconnected to move in directly proportional relationship with respect toeach other, the position of one of said parts determining the quantityof fuel delivered by said pump means for each Working stroke 01 thecylinder, the position of the other of said parts determining theposition of adjustment of said abutment relative to said inlet openingand said other of said parts determining a position of adjustment ofsaid abutment for causing said valve member to be fully opened when saidregulating mechanism is adjusted to provide a fuel supply suitable forsubstantially full load operation of the engine.

16. In an internal combustion engine having a working cylinder, meansfor providing a passage for volatile fuel and air to the engine andhaving an. inlet for air, a plunger pump for supplying a measuredquantity of fuel to the cylinder for each working stroke, a valve forcontrolling said inlet, said valve comprising a reciprocable valvemember adapted to open under the influence or pressure of air admittedthrough said inlet, said valve providing an inlet opening for flow ofair increasing in size in'substantially direct proportion with movementof said valve member away from closed position, mechanism for regulatingsaid pump means and said valve comprising a first part movable to alterthe effective stroke of said pump. whereby to regulate the quantity offuel delivered by the pump for each working stroke and asecond partoperatively connected with said first part so as to move insubstantially directly proportional relationship therewith, said secondpart providing an abutment, and a loading spring for said valve, saidspring reacting against said abutment and tending to close the valve andsaid second part having a position rendering said loading springineiiective to move said valve member from fully open position when saidregulating mechanism is adjusted to pro- .vide a fuel supply suitablefor substantially full load operation of the engine.

JONAS ELIAS I-ESSELMAN.

